--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libervia/backend/core/core_types.py	Fri Jun 02 11:49:51 2023 +0200
@@ -0,0 +1,66 @@
+#!/usr/bin/env python3
+
+# Libervia types
+# Copyright (C) 2011  Jérôme Poisson (goffi@goffi.org)
+
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Affero General Public License for more details.
+
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+from collections import namedtuple
+from typing import Dict, Callable, Optional
+from typing_extensions import TypedDict
+
+from twisted.words.protocols.jabber import jid as t_jid
+from twisted.words.protocols.jabber import xmlstream
+from twisted.words.xish import domish
+
+
+class SatXMPPEntity:
+
+    profile: str
+    jid: t_jid.JID
+    is_component: bool
+    server_jid: t_jid.JID
+    IQ: Callable[[Optional[str], Optional[int]], xmlstream.IQ]
+
+EncryptionPlugin = namedtuple("EncryptionPlugin", ("instance",
+                                                   "name",
+                                                   "namespace",
+                                                   "priority",
+                                                   "directed"))
+
+
+class EncryptionSession(TypedDict):
+    plugin: EncryptionPlugin
+
+
+# Incomplete types built through observation rather than code inspection.
+MessageDataExtra = TypedDict(
+    "MessageDataExtra",
+    { "encrypted": bool, "origin_id": str },
+    total=False
+)
+
+
+MessageData = TypedDict("MessageData", {
+    "from": t_jid.JID,
+    "to": t_jid.JID,
+    "uid": str,
+    "message": Dict[str, str],
+    "subject": Dict[str, str],
+    "type": str,
+    "timestamp": float,
+    "extra": MessageDataExtra,
+    "ENCRYPTION": EncryptionSession,
+    "xml": domish.Element
+}, total=False)